Question on bleach and pH

adamt

Active member
Feb 10, 2016
37
Los Angeles, CA
#1
As far as bleach, I'm wondering why that is the preferred sanitation method around here. I've been using it since I found this site and everything is fine, but it seems more expensive to me. I go through at least 6 gallons a month at about $3.30 per gallon. I'm sure I'll be using more during the summer months. Are pucks recommended too?

And is there a reason why my pH always seems to creep up to 8.0? Every week I'm adding acid to get it down. Is this normal? How do I get it to stabilize?

Readings this morning:

FC - 5
pH - 8
TA - 80
CH - 325
CYA - 60
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
20,327
San Dimas, CA (LA County)
#2
Bleach is preferred because the only byproduct is salt. The only thing purer is Chlorine gas, which brings a whole 'nother set of problems. Powdered forms of chlorine leave behind either Calcium or Cyanuric Acid. And Salt, as well. Pool School - How to Chlorinate Your Pool

Your CYA is already at 60. You don't want it to go much higher. Higher CYA means higher FC levels are needed to keep it algae free and sanitary. If you try raising FC with pucks, you've just raised the CYA, which means you need still higher FC levels. And then you get stuck in an endless spiral that ends with a green cloudy pool, the pool store telling you you need to drain because of "Chlorine Lock" and us telling you to drain because of CYA buildup.

In season, I use about a quart of 12.5% per day. I pay $3.70/gallon in the returnable HASA jugs. A buck a day isn't bad if you ask me. In the winter, I use hardly any.

Rising pH is a fact of life. Test your fill water. Odds are it's higher pH than your pool, and higher TA. So every time you add water, you're driving up pH and TA and you need to add acid. Since I got my TA driven down to 60, it's been easy to maintain the pH, but it's still pretty much a weekly thing.
 

cowboycasey

Gold Supporter
LifeTime Supporter
TFP Guide
Jul 3, 2013
3,430
Fletcher, OK
#3
Hey there, great questions and that is why I love this site :)

Bleach, all forms of chlorine cost almost the same in the end... with that said, in your area you may have a better option, a pool store near you may have 12% liquid chlorine, it is exactly the same as bleach but you will use less of the 12% than the 8% bleach :) here is the HASA locater.. http://www.hasapool.com/dealer_locator_hasa.php you want to buy the 2.5 gallon carboys and maybe only 2 at a time, the 12% will go down faster than the 8% as it sits...you don't want to buy the whole summer worth :)

Yes, you could use pucks but it will cost you in the end when you have to drain half your pool water once or twice a year and you know how much that can cost in CA, even if you could...

Your PH rise, you can lower your TA a little more to 70 and if your PH is still rising fast take your TA to 60... here is the fastest and easiest way to do it..
Pool School - Lower Total Alkalinity

I hope this helps :)
 

jtaves85mcss

LifeTime Supporter
May 12, 2012
189
Cincinnati, OH
#4
+1 on the directions and link from cowboycasey. Once you find the sweet spot with a little lower TA you will find that Ph rise becomes minimal an you may only have to add MA once every three or four weeks to keep your Ph around 7.5. I finally got mine to almost auto pilot last year, adding 12 oz full strength MA once a month.
 

camueller

Well-known member
May 11, 2016
486
Troy IL
#5
So I've read that the Ph of bleach is around 12, depending on the manufacturer. But that it has to be so that the chlorine is stable. Doesn't adding this bleach itself raise your Ph?

I've yet to start my pool with the TFP method, but I've been warned that is the downside to using bleach/liquid chlorine. That may or may not be true. Perhaps the dilution in the water is enough to even it out?
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
41,197
Tucson, AZ
#6
When you add bleach to raise the FC, the pH does go up a little. But, when the FC is consumed, that process actually lowers the pH. So the net effect is that bleach is basically pH neutral in the pool.
 

Cinic

Silver Supporter
Jul 24, 2015
194
Tempe, AZ
#7
My pH has been much more stable after lowering the TA from the 80-90 range down to about 70. It'll go up to 7.6-7.7 from 7.5 in a week or so. Then I add 8 or 16 oz of MA. With the higher TA it was going up much more quickly.

I will fight rising pH and TA (or is it TA and pH?) more when it gets really hot and evaporation requires a lot more of my high TA fill water. But at least now I know where my pool is more comfortable and I can stay ahead of it.